Some results on the ordering of the Laplacian spectral radii of unicyclic graphs

نویسندگان

  • Ying Liu
  • Jia-Yu Shao
  • Xi-Ying Yuan
چکیده

A unicyclic graph is a graph whose number of edges is equal to the number of vertices. Guo Shu-Guang [S.G. Guo, The largest Laplacian spectral radius of unicyclic graph, Appl. Math. J. Chinese Univ. Ser. A. 16 (2) (2001) 131–135] determined the first four largest Laplacian spectral radii together with the corresponding graphs among all unicyclic graphs on n vertices. In this paper, we extend this ordering by determining the fifth to the ninth largest Laplacian spectral radii together with the corresponding graphs among all unicyclic graphs on n vertices. c © 2007 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 156  شماره 

صفحات  -

تاریخ انتشار 2008